/*++

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            HackSys Extreme Vulnerable Driver

Author : Ashfaq Ansari
Contact: ashfaq[at]hacksys[dot]io
Website: https://hacksys.io/

Copyright (C) 2021-2023 HackSys Inc. All rights reserved.
Copyright (C) 2015-2020 Payatu Software Labs LLP. All rights reserved.

This program is free software: you can redistribute it and/or modify it under the terms of
the GNU General Public License as published by the Free Software Foundation, either version
3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program.
If not, see <http://www.gnu.org/licenses/>.

THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

See the file 'LICENSE' for complete copying permission.

Module Name:
    MemoryDisclosureNonPagedPool.c

Abstract:
    This module implements the functions to demonstrate
    memory disclosure in NonPagedPool vulnerability.

--*/

#include "MemoryDisclosureNonPagedPool.h"

#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE, TriggerMemoryDisclosureNonPagedPool)
#pragma alloc_text(PAGE, MemoryDisclosureNonPagedPoolIoctlHandler)
#endif // ALLOC_PRAGMA


/// <summary>
/// Trigger the Memory Disclosure in NonPagedPool Vulnerability
/// </summary>
/// <param name="UserOutputBuffer">The pointer to user mode output buffer</param>
/// <param name="Size">Size of the user mode buffer</param>
/// <returns>NTSTATUS</returns>
NTSTATUS
TriggerMemoryDisclosureNonPagedPool(
    _In_ PVOID UserOutputBuffer,
    _In_ SIZE_T Size
)
{
    PVOID KernelBuffer = NULL;
    NTSTATUS Status = STATUS_SUCCESS;

    PAGED_CODE();

    __try
    {
        DbgPrint("[+] Allocating Pool chunk\n");

        //
        // Allocate Pool chunk
        //

        KernelBuffer = ExAllocatePoolWithTag(
            NonPagedPool,
            (SIZE_T)POOL_BUFFER_SIZE,
            (ULONG)POOL_TAG
        );

        if (!KernelBuffer)
        {
            //
            // Unable to allocate Pool chunk
            //

            DbgPrint("[-] Unable to allocate Pool chunk\n");

            Status = STATUS_NO_MEMORY;
            return Status;
        }
        else
        {
            DbgPrint("[+] Pool Tag: %s\n", STRINGIFY(POOL_TAG));
            DbgPrint("[+] Pool Type: %s\n", STRINGIFY(NonPagedPool));
            DbgPrint("[+] Pool Size: 0x%zX\n", (SIZE_T)POOL_BUFFER_SIZE);
            DbgPrint("[+] Pool Chunk: 0x%p\n", KernelBuffer);
        }

        //
        // Work on the kernel buffer
        //

        RtlFillMemory(KernelBuffer, (SIZE_T)POOL_BUFFER_SIZE, 0x41);

        //
        // After working on the kernel buffer, it's time to give
        // the output to the user
        //

        //
        // Verify if the output buffer resides in user mode
        //

        ProbeForWrite(UserOutputBuffer, (SIZE_T)POOL_BUFFER_SIZE, (ULONG)__alignof(UCHAR));

        DbgPrint("[+] UserOutputBuffer: 0x%p\n", UserOutputBuffer);
        DbgPrint("[+] UserOutputBuffer Size: 0x%zX\n", Size);
        DbgPrint("[+] KernelBuffer: 0x%p\n", KernelBuffer);
        DbgPrint("[+] KernelBuffer Size: 0x%zX\n", (SIZE_T)POOL_BUFFER_SIZE);

#ifdef SECURE
        //
        // Secure Note: This is secure because the developer is passing a size
        // equal to size of the allocated Pool chunk to RtlCopyMemory()/memcpy().
        // Hence, there will be no out of bound read of kernel mode memory
        //

        RtlCopyMemory(UserOutputBuffer, KernelBuffer, (SIZE_T)POOL_BUFFER_SIZE);
#else
        DbgPrint("[+] Triggering Memory Disclosure in NonPagedPool\n");

        //
        // Vulnerability Note: This is a vanilla memory disclosure vulnerability
        // because the developer is passing the user supplied value directly to
        // RtlCopyMemory()/memcpy() without validating if the size is greater or
        // equal to the size of the allocated Pool chunk which will result in reading
        // more data from kernel mode and passing to user mode memory which causes memory
        // disclosure vulnerability
        //

        RtlCopyMemory(UserOutputBuffer, KernelBuffer, Size);
#endif

        if (KernelBuffer)
        {
            DbgPrint("[+] Freeing Pool chunk\n");
            DbgPrint("[+] Pool Tag: %s\n", STRINGIFY(POOL_TAG));
            DbgPrint("[+] Pool Chunk: 0x%p\n", KernelBuffer);

            //
            // Free the allocated Pool chunk
            //

            ExFreePoolWithTag(KernelBuffer, (ULONG)POOL_TAG);
            KernelBuffer = NULL;
        }
    }
    __except (EXCEPTION_EXECUTE_HANDLER)
    {
        Status = GetExceptionCode();
        DbgPrint("[-] Exception Code: 0x%X\n", Status);
    }

    return Status;
}


/// <summary>
/// Memory Disclosure NonPagedPool Ioctl Handler
/// </summary>
/// <param name="Irp">The pointer to IRP</param>
/// <param name="IrpSp">The pointer to IO_STACK_LOCATION structure</param>
/// <returns>NTSTATUS</returns>
NTSTATUS
MemoryDisclosureNonPagedPoolIoctlHandler(
    _In_ PIRP Irp,
    _In_ PIO_STACK_LOCATION IrpSp
)
{
    SIZE_T Size = 0;
    PVOID UserOutputBuffer = NULL;
    NTSTATUS Status = STATUS_UNSUCCESSFUL;

    UNREFERENCED_PARAMETER(Irp);
    PAGED_CODE();

    UserOutputBuffer = Irp->UserBuffer;
    Size = IrpSp->Parameters.DeviceIoControl.OutputBufferLength;

    if (UserOutputBuffer)
    {
        Status = TriggerMemoryDisclosureNonPagedPool(UserOutputBuffer, Size);
    }

    return Status;
}
